Tank assembly method and apparatus

ABSTRACT

Steel cylinders placed end-to-end on rollers, are pushed together between a headstock and tailstock, being rolled, pried and hammered, as and where needed.

United States Patent Herdman et a].

[ 1 Jan.23,1973

TANK ASSEMBLY METHOD AND APPARATUS Inventors: William R. Herdman;Charles W. Sonnenberg, both of Indianapolis, Ind.

Kennedy Tank & Manufacturing Company, Inc., Indianapolis, Ind.

Filed: Feb. 24, 1971 Appl. No.: 118,378

Assignee:

U.S. Cl ..29/43l Int. Cl. ..B23p 19/00 Field of Search ..29/43l, 200 R,240

[56] References Cited UNITED STATES PATENTS 2,287,197 6/1942 Sandberg..29/43l 2,287,198 6/1942 Sandberg ..29/431 Primary Examiner-Thomas HEager AttorneyWoodard, Weikart, Emhardt & Naughton [57] ABSTRACT Steelcylinders placed end-to-end on rollers, are pushed together between aheadstock and tailstock, being rolled, pried and hammered, as and whereneeded.

3 Claims, 7 Drawing Figures PATENIEDJMIZEI ms 3.711.933

sum 1 OF 2 INVENTORS l/mes W LSbA/A/EA/ASP BY VV/LLmM E #mamm ATTORNEYSPATENTEUJAH23 1975 3,711,933

sum 2 OF 2 I NV EN TORS [ll/72L 55 W SONNENBEZG BY WILL/AM IZ/EEDMAA/a/M/MA,AIMZ:,W m /an ATTORNEYS TANK ASSEMBLY METHOD AND APPARATUSBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to assembly of steel tanks, and more particularly to a fixtureand method for facilitating such assembly.

2. Description of the Prior Art The pressing of heads or ends on a tankin a fixture is known in the art, as is the assembly of cylindricalpieces by fitting them together end-to-end. We believe that the assemblyof large tanks by pressing together a number of cylinders, is not sowell known, if known at all heretofore. Yet we have found someadvantages in terms of time savings, quality and convenience by forcingand fitting together a plurality of tank rings in a fixture.

SUMMARY OF THE INVENTION Described briefly, in a typical embodiment ofthe method of the present invention, the headstock and tailstock of thefixture are separated by a sufficient distance to place therebetween aplurality of cylinders to be fitted together. The cylinders are placedon cradle rolls, and each cylinder following the first cylinder isdisposed with an inwardly offset leading end portion disposed partiallyinside the tail end portion of the cylinder immediately ahead of it, ata point below the centerline of the cylinder immediately ahead of it.Then the cylinders are clamped together, the rolls (and thereby thecylinders thereon) are turned, and the leading ends are worked into thetail ends as needed until the cylinders fit together properly completelyaround their circumferences at each joint. Then they are securedtogether, as by tack welding, for example, following which the movableportion of the headstock is retracted.

The cylinders are then pushed against the retracted head-stock portion,by means of a jack on the tailstock. An end cap is placed on the rollsbetween the tailstock and the rear cylinder. The flange on the end capis held in overlapping relation with a portion of the wall of the lastcylinder at the tail end of the last cylinder. While being so held, therolls are turned to feed the tail end cap onto the last cylinder. Oncedisposed in overlapping relationship around the entire tail end of thelast cylinder, the headstock portion is again extended to move thecylinder assembly toward the tailstock and clamp the tail end cap firmlyin place while it is secured by tack welding or the like.

A similar procedure is followed at the opposite end,

where after retraction of the headstock portion, a head end cap isinserted between the front end of the first cylinder and the headstockportion, worked into place, clamped in place by the headstock portion,and secured to the first cylinder as by tack welding, for example.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simple schematicelevational view of the fixture of the present invention with fourcylinders placed thereon for assembly into a tank.

FIG. 2 is an enlarged elevational view thereof with a fragment removedfrom the center to conserve space on the drawing sheet.

FIG. 3 is a section taken at line 3-3 in FIG. 2 and viewed in thedirection of the arrows.

FIG. 4 is an enlarged detail showing the way in which the cylinders areplaced together for clamping.

FIG. 5 is an enlarged view showing the way the tail end cap is placed onthe tail end cylinder upon initial assembly thereof.

FIG. 6 is an enlarged view showing the way the head end cap is placed onthe head end cylinder upon initial assembly thereof.

FIG. 7 is a fragmentary schematic showing the location of the hydraulicjack on the tailstock.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, aheadstock 11 is affixed to a pair of longitudinally extending base framerails 12, and a tailstock 13 is mounted on the rails so that it can bemoved toward and away from the headstock as needed to accommodate thenumber of rings or cylinders 14, 16, 17 and 18 to be assembled into atank. The headstock includes a tank-engaging frame or member 19 which ismovable toward and away from the headstock by means to be described. Thetailstock has a similar tank-engaging member 21 mounted thereto.

Referring now to FIGS. 2 and 3, the headstock 11 includes a structureaffixed to rails 12 and to which a scissors or spider linkage 22 ismounted for controlling movement of the tank clamp member 19 which issupported on the rails 12 by a pair of wheels 23, one wheel on each sideof the member 19. A fluid actuator 24 is of a double acting type capableof extending or retracting the piston rod 26 connected to the member 19to push the member 19 in the direction of arrow 27 away from thehead-stock, or pull it in the direction of arrow 28 toward the headstock28. The upper ends of the scissors members are pinned to the headstockand to the member 19 to pivot on parallel horizontal axes through points29 and 31. The scissors members are pivoted together on horizontal axis32. The lower ends are mounted to the headstock and to member 19 in amanner such that they can move upwardly and downwardly to some extendwhile pivoting at the same time. Various ways and means can be employedfor doing this and it is merely shown schematically as pins in slots 33and 34.

Two wheels 36 are provided at the front end of the tailstock 13, one oneach side and riding on the respective I-beams 12 serving as thelongitudinal members of the base frame. Similarly two wheels 37 areprovided at the rear. Two wheels 39 mounted to the tailstock areprovided at each side under the inwardly turned upper flange of each ofthe I-beams to hold the tailstock down on the bed rails 12. A lockingpin 41 is provided through an aperture in the downwardly projectingplate 42 of the tailstock and receivable in any one of a plurality ofapertures 43 spaced along the bed rails. Apertures are spaceddifferently on the rails with respect to the apertures of the projectingplate 42, in order to provide a greater number of adjustments, ifdesired, by inserting lock pins.

Member 21 is pinned at 44 to the tailstock and is secured by a pair ofbolts 46 which can be turned in or out to pivot the member 21 back andforth about axis 44 in the direction of arrows 47 to whatever extend isneeded to provide the desired upstanding surface to be engaged by thetank cylinders during the fit-up operation. At the bottom of thetailstock 13, as best shown in FIG. 7, there is a hydraulic jack 48having a pusher plate 49 on the ram thereof to engage the end of acylinder such as 18 and enable pushing it toward the headstock.

As better shown in FIG. 3, member 19 is designed in a shape such thatthe fixture can accept small tanks of the order of 48 inches indiameter, or very large tanks of the order of and ya feet in diameter.In either event, the cylinders are cradled between the longitudinallyextending rolls 51. A drive motor 52 (FIG. 2) is provided with suitablepower transmission facilities to simultaneously drive both rolls 51 bymeans of the chains 53, so that the rolls can be rotated in the samedirection, either clockwise in the direction of arrow 54 in FIG. 3, orcounterclockwise in the direction of arrow 56.

OPERATION In the use of the apparatus, the tailstock is moved away fromthe headstock far enough to provide sufficient space between them forconvenient placement of the number of cylinders to be used in theassembly operation. The first cylinder 14 is placed on the rollsimmediately adjacent the headstock with the member 19 retracted in thedirection of arrow 28. The next cylinder 16 is placed on the rolls withits leading or front end positioned so that the offset portion 57projects inside the tail end portion of the cylinder 14 immediatelyahead of it, below a horizontal centerline through cylinder 14. Thisfacilitates assembly according to the method of the present invention.

Then the cylinder 17 is placed on the rolls with its leading or frontend offset portion just inside the tail end of cylinder 16 inessentially the same manner as shown in FIG. 4. Then the cylinder 18 isplaced on the rolls and partially interfitted with tank cylinder 17 in Vthe same manner. Then the tailstock is rolled into position snug againstthe tail end of the cylinder 18. Then the pressure is applied inactuator 24 in a direction to roll the headstock portion 19 in thedirection of arrow 27 to clamp the cylinders together.

Then the roll drive motor 52 is operated to turn the rolls and therebyturn the cylinders on the roll. At the same time, by making whatever useis needed of prybars and a hammer, the leading ends of the variouscylinders can be worked into the tail ends of the cylinders immediatelyahead of them until finally all cylinders are snapped together so thatthere is an overlapping relationship between the rear end of eachcylinder and the offset or axially extending flange at the front orleading end of the cylinder next behind it. Then these cylinders can betack welded together at the three joints to secure them in assembly. Noeffort need be made at this time to provide a complete welded joint forliquid sealing purposes around the entire circumference of each joint.That can be done after the assembly is removed from the illustratedfixture, if desired.

Once all of the cylinders are securely tacked together, actuator 24 isoperated to retract the headstock portion 19, rolling it in thedirection of arrow 28. Then the hydraulic jack 48 is operated to pushthe assembly of tanks away from the tailstock toward the headstock andagain into abutment with member 19. Then the jack is returned to itsoriginal condition.

Then, with the tailstock remaining in position, the rear end cap 58, ofthe tank is placed on the rolls and the axially projecting circularflange 59 thereof is placed in overlapping relationship with the rearend of cylinder 18 at a point 61 immediately above the rolls. Then therolls are turned in the direction of arrow 56 in FIG. 3 so that the endcap and cylinder move clockwise in the direction of arrow 54. Theoverlapping portion moves down to be sandwiched between the rolls andthe cylinder 18. As the rolls continue to turn, manual force is appliedin the direction of arrow 28 to continue to feed the flange, and therebythe rear end cap, onto the end of the cylinder 18. Once this has beenaccomplished around the entire circumference of the cylinder, actuator24 of the headstock is again operated to roll the member 19 rearwardlyin the direction of arrow 27 to force the tank 18, and end cap 58therewith, against the tailstock member 21. This drives the end cap homeand it can then be tack welded in place.

Then the headstock member 19 is again retracted and the front end cap 62is placed on the rolls, and the flange 63 thereof overlapped with theleading edge of the cylinder 14. Again the roll drive motor is turned onto turn the rolls in the clockwise direction of arrow 56 as manualeffort is applied in the direction of arrow 27 to feed the front end cap62 onto the cylinder 14. Once this is finished, actuator 24 is actuatedto drive the member 19 in the direction of arrow 27 to force home theend cap 62 onto the cylinder 14. Then the front end cap is secured inplace by tack welding, for example.

Finish welding of the scams or joints, provision of the various portsand fittings along the tank, can then be accomplished on the fixtureshown, or the tank can be moved elsewhere for this purpose. Dependingupon the number of cylinders to be assembled, it is possible that theextent of travel of the jack mounted to the tailstock, or the actuatorand piston on the headstock, may not be sufficient to completely closethe gaps or move the cylinder assembly the extent needed. In that event,the tailstock locking pins can be removed and the tailstock rolledtoward the headstock to whatever extent is needed, when needed.

While the invention has been disclosed and described in some detail inthe drawings and foregoing description, they are to be considered asillustrative and not restrictive in character, as other modificationsmay readily suggest themselves to persons skilled in this art and withinthe broad scope of the invention.

The invention claimed is:

l. A method of assembling a tank and comprising the steps of:

placing a plurality of cylinders on cradle rolls, with the leading endof each cylinder disposed partially inside the tail end of the cylinderimmediately ahead of it, at a point below the center of said cylinderahead;

clamping said cylinders between a headstock and a tail-stock;

turning said rolls to turn said cylinders in unison;

and working the leading ends into the tail ends around the circumferenceas the cylinders turn on said rolls; and

affixing said cylinders together to make an assembly.

2. The method of claim 1 and further comprising the steps of:

retracting the headstock portion engaging the first of saidcylinders andthereby disengaging said headstock portion from said first cylinder;

pushing the cylinder assembly away from the tailstock and against saidheadstock portion;

placing a first end cap on said rolls between said tailstock and thelast of said cylinders;

overlapping an axially extending flange of said end cap with a wallportion of said last cylinder at the tail end thereof;

turning the rolls in a direction moving the overlapped portion onto saidrolls and urging the cap toward the cylinder, while turning, to feed thecap on; and

advancing said headstock portion to clamp the first end cap fully inplace on said last cylinder. 3. The method of claim 2 and furthercomprising the steps of:

securing said first end cap on said last cylinder;

retracting said headstock portion;

placing a second end cap on said rolls between said headstock portionand said first cylinder;

overlapping an axially extending end cap flange over a wall portion ofsaid first cylinder at the head end of said first cylinder;

turning the rolls in a direction moving the overlapped portion of saidsecond end cap onto said rolls, and urging said second end cap towardsaid first cylinder while turning, to feed said second end cap advancingsaid headstock portion to clamp said second end cap fully in place onsaid first cylinder; and

securing said second end cap on said first cylinder.

1. A method of assembling a tank and comprising the steps of: placing aplurality of cylinders on cradle rolls, with the leading end of eachcylinder disposed partially inside the tail end of the cylinderimmediately ahead of it, at a point below the center of said cylinderahead; clamping said cylinders between a headstock and a tail-stock;turning said rolls to turn said cylinders in unison; and working theleading ends into the tail ends around the circumference as thecylinders turn on said rolls; and affixing said cylinders together tomake an assembly.
 2. The method of claim 1 and further comprising thesteps of: retracting the headstock portion engaging the first of saidcylinders and thereby disengaging said headstock portion from said firstcylinder; pushing the cylinder assembly away from the tailstock andagainst said headstock portion; placing a first end cap on said rollsbetween said tailstock and the last of said cylinders; overlapping anaxially extending flange of said end cap with a wall portion of saidlast cylinder at the tail end thereof; turning the rolls in a directionmoving the overlapped portion onto said rolls and urging the cap towardthe cylinder, while turning, to feed the cap on; and advancing saidheadstock portion to clamp the first end cap fully in place on said lastcylinder.
 3. The method of claim 2 and further comprising the steps of:securing said first end cap on said last cylinder; retracting saidheadstock portion; placing a second end cap on said rolls between saidheadstock portion and said first cylinder; overlapping an axiallyextending end cap flange over a wall portion of said first cylinder atthe head end of said first cylinder; turning the rolls in a directionmoving the overlapped portion of said second end cap onto said rolls,and urging said second end cap toward said first cylinder while turning,to feed said second end cap on; advancing said headstock portion toclamp said second end cap fully in place on said first cylinder; andsecuring said second end cap on said first cylinder.